Search Publications
Determination of the SO/PHI-HRT wavefront degradation using multiple defocused images
Schmidt, W.; Woch, J.; Solanki, S. K. +50 more
Context. The Polarimetric and Helioseismic Imager on board the Solar Orbiter mission (SO/PHI) offers refocusing capabilities to cope with the strongly varying thermal environment of the optical system along the spacecraft's elliptical orbit. The series of images recorded during in-flight focus calibrations can be employed for phase diversity analy…
Photometric recalibration of VPHAS+ u-band photometry with the stellar colour regression method and Gaia DR3
Yuan, Hai-Bo; Chen, Bing-Qiu; Huang, Bo-Wen
The u-band magnitude is vital for determining stellar parameters and investigating specific astronomical objects. However, flux calibration in the u band for stars in the Galactic disc presents significant challenges. In this study, we introduce a comprehensive recalibration of u-band photometric magnitudes of the VPHAS+ Data Release 4, employing …
Measuring the impact of laser relative intensity noise on heterodyne interferometers using differential wavefront sensing
Heinzel, G.; Hewitson, M.; Wissel, L.
Laser-intensity fluctuations cause undesired phase noise even in balanced heterodyne interferometers. However, in space missions in particular, such as LISA Pathfinder or LISA, direct measurements of these fluctuations at the relevant frequencies are often not available. Hence, it can be challenging to estimate their impact on the interference pha…
Determining the Structure of the Atmosphere Exoplanet HD 189733b Based on Multicolor Photometric Transit Observations
Bekesov, E. V.
In this paper, we analyze and interpret light curves obtained by observing with the HST telescope the transit of exoplanet HD 189733b across the disk of the star. Observations are carried out in a wide wavelength range of 5500–10 500 Å, which makes it possible to identify the relation between the wavelength and the data obtained during the interpr…
Luminosity dependent cyclotron line in Swift J1626.6‑5156
Paul, Biswajit; Tobrej, Mohammed; Rai, Binay +3 more
We studied the timing and spectral properties of the Be/X-ray pulsar Swift J1626.6‑5156 using the NICER observations of its 2021 outburst. The most important observation is the positive correlation of the centroid energy of the fundamental cyclotron line with the luminosity. This observation agrees with the usual positive correlation of the centro…
Temperature Intermittent Structures in the Fast Solar Wind
Wang, Xin; Wang, Yuxin; Song, Dongze +1 more
In the solar wind turbulence, proton temperature fluctuations are highly intermittent, especially at small scales in the inertial range. This phenomenon may contain information about solar wind intermittent heating. However, the physical nature of the temperature intermittency is not yet clear. Based on the measurements from Solar Orbiter between …
Radial velocity analysis of stars with debris discs
Jones, Hugh R. A.; Bisht, Deepak
This study aims to identify potential exoplanet signals from nearby stars with resolved debris discs. However, the high activity of many stars with debris discs limits the detection of periodic signals. Our study is constrained to a sample of 29 stars that have appropriate radial velocity data and debris disc measurements sufficient to resolve the…
XMM-Newton and NuSTAR discovery of a likely IP candidate XMMU J173029.8–330920 in the Galactic disc
Hailey, Charles J.; Mori, Kaya; Rea, Nanda +7 more
Aims. We aim to characterise the population of low-luminosity X-ray sources in the Galactic plane by studying their X-ray spectra and periodic signals in the light curves. Methods. We are performing an X-ray survey of the Galactic disc using XMM-Newton, and the source XMMU J173029.8–330920 was serendipitously discovered in our campaign. We perform…
Correction to: Stellar clustering and the kinematics of stars around Collinder 121 using Gaia DR3
Ward-Thompson, Derek; Fleming, Graham D.; Kirk, Jason M.
Gemini Planet Imager Observations of a Resolved Low-inclination Debris Disk around HD 156623
Crotts, Katie A.; Matthews, Brenda C.; Duchêne, Gaspard +12 more
The 16 Myr old A0V star HD 156623 in the Scorpius–Centaurus association hosts a high-fractional-luminosity debris disk, recently resolved in scattered light for the first time by the Gemini Planet Imager (GPI) in polarized intensity only. We present a new analysis of the GPI H-band polarimetric detection of the HD 156623 debris disk, with particul…